The use of plastic and other non-rigid piping and conduit for various applications in building construction, such as water distribution piping, has become widespread in recent years. The development of long life plastic piping for use in water distribution, for example, has improved the speed and ease with which plumbing may be installed in various building structures and other installations. The relative ease with which plastic water distribution conduit may be bent to change the direction of the conduit run has greatly reduced or eliminated the need for fittings for changing the direction of the conduit run and the associated operations necessary for installing the conduit such as is required with rigid steel pipe, for example.
However, the bendability of plastic tubing has presented certain problems associated with its installation. For example, the elasticity of plastic tubing, such as polybutylene tubing used for water conduit, requires that the tubing be adequately supported during and after the bending operation. This is true, particularly, if the tubing is being run through a concrete slab which is to be poured after the tubing is laid over the area to be occupied by the slab and extended to the various plumbing outlets within the building. Since the conduit runs must be installed before the slab is poured, it is necessary to support the tubing at the bends until the concrete solidifies around the tubing itself. For example, when water distribution conduit is laid within an area to be occupied by a concrete slab, the run of the conduit is preferably formed at right angles so that the conduit may project from the upper surface of the slab for connection to various fixtures within the structure supported by the slab. It is therefore highly desirable to provide a support which will hold the conduit in the proper position and bent at substantially right angles from the horizontal run and which support may be encased by the concrete when the slab is poured.
Another problem associated with bending flexible plastic as well as certain types of metal tubing pertains to the tendency for the tubing to kink or undergo plastic deformation if the bend radius is not carefully controlled and the conduit adequately supported during the bending operation. In particular, it has been a problem in the bending of polybutylene water distribution conduit to prevent the kinking of the conduit when making bends of various angles and in particular when the conduit is bent at right angles to change the direction of the conduit run.
The present invention is adapted to overcome the aforementioned problems in the installation of plastic non-rigid tubing or conduit used for water distribution. Moreover, the present invention may also be used for the bending and support of conduit used for various other applications such as, for example, the containment of electrical wiring and the like.